GB2445617A - Process for producing preparing sulfonyl ethers from sulfonic acids - Google Patents

Process for producing preparing sulfonyl ethers from sulfonic acids Download PDF

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Publication number
GB2445617A
GB2445617A GB0700515A GB0700515A GB2445617A GB 2445617 A GB2445617 A GB 2445617A GB 0700515 A GB0700515 A GB 0700515A GB 0700515 A GB0700515 A GB 0700515A GB 2445617 A GB2445617 A GB 2445617A
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United Kingdom
Prior art keywords
substituted
unsubstituted
ether
sulfonyl
sulfonyl ether
Prior art date
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Granted
Application number
GB0700515A
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GB2445617B (en
GB0700515D0 (en
Inventor
Antony Warr
Peter Mccormack
Jonathan Eddolls
Elliot Latham
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Phoenix Chemicals Ltd
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Phoenix Chemicals Ltd
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Priority to GB0700515.0A priority Critical patent/GB2445617B/en
Publication of GB0700515D0 publication Critical patent/GB0700515D0/en
Priority to PCT/EP2008/050152 priority patent/WO2008084048A1/en
Priority to EP08701318A priority patent/EP2121587A1/en
Priority to AU2008204534A priority patent/AU2008204534B2/en
Priority to CA002674873A priority patent/CA2674873A1/en
Priority to JP2009545169A priority patent/JP2010515703A/en
Priority to CNA2008800020582A priority patent/CN101610994A/en
Priority to US12/522,899 priority patent/US20100094038A1/en
Publication of GB2445617A publication Critical patent/GB2445617A/en
Application granted granted Critical
Publication of GB2445617B publication Critical patent/GB2445617B/en
Expired - Fee Related legal-status Critical Current
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    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C303/00Preparation of esters or amides of sulfuric acids; Preparation of sulfonic acids or of their esters, halides, anhydrides or amides
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C309/00Sulfonic acids; Halides, esters, or anhydrides thereof
    • C07C309/01Sulfonic acids
    • C07C309/02Sulfonic acids having sulfo groups bound to acyclic carbon atoms
    • C07C309/03Sulfonic acids having sulfo groups bound to acyclic carbon atoms of an acyclic saturated carbon skeleton
    • C07C309/07Sulfonic acids having sulfo groups bound to acyclic carbon atoms of an acyclic saturated carbon skeleton containing oxygen atoms bound to the carbon skeleton
    • C07C309/09Sulfonic acids having sulfo groups bound to acyclic carbon atoms of an acyclic saturated carbon skeleton containing oxygen atoms bound to the carbon skeleton containing etherified hydroxy groups bound to the carbon skeleton
    • C07C309/10Sulfonic acids having sulfo groups bound to acyclic carbon atoms of an acyclic saturated carbon skeleton containing oxygen atoms bound to the carbon skeleton containing etherified hydroxy groups bound to the carbon skeleton with the oxygen atom of at least one of the etherified hydroxy groups further bound to an acyclic carbon atom
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C303/00Preparation of esters or amides of sulfuric acids; Preparation of sulfonic acids or of their esters, halides, anhydrides or amides
    • C07C303/26Preparation of esters or amides of sulfuric acids; Preparation of sulfonic acids or of their esters, halides, anhydrides or amides of esters of sulfonic acids
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C67/00Preparation of carboxylic acid esters
    • C07C67/12Preparation of carboxylic acid esters from asymmetrical anhydrides

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Abstract

A method of preparing a sulfonyl ether comprising the steps of: <SL> <LI>i) reacting a sulfonic acid with an anhydride, under continuous vacuum distillation conditions, to form a carboxysulfonate; <LI>ii) reacting the carboxysulfonate with an optionally substituted cycloalkane ring containing at least 3 heteroatoms to form a sulfonyl ether pre-mix comprising a sulfonyl ether and at least two additional reaction products each containing at least one ether linkage; <LI>iii) subjecting the pre-mix to continuous vacuum distillation conditions to remove at least some of the additional reaction products from the sulfonyl ether pre-mix to provide a crude sulfonyl ether product; and <LI>iv) purifying the crude sulfonyl ether product. </SL> The preferred sulfonic acid is a methanesulfonic acid and the preferred sulfonyl ether is bis(methanesulfonylmethyl)ether (BSME). The preferred carboxysulfonate is acetyl methane sulfonate (AMS). The preferred cycloalkane comprising three hetero atoms is trioxane.

Description

Synthesis This invention relates to a process for synthesising sulfonyl
ethers More particularly, this invention relates to a process of synthesizing sulfonyl ethers from sulfonic acids Sulfonyl ethers have numerous applications and are employed in the synthesis of compounds for use in a wide range of technical fields. For example, as confirmed in Japanese Patent Nos. 03-178958, 03-178959, 03-123768 and 03- 123769, sulfonyl ethers may be used in the synthesis of methyl ether derivatives which are useful in the field of photography as gelatin membrane hardeners, development accelerators and chemical sens:t:zcrs Thc use of sulfony! ethers as photographic gelatin hardeners is also disclosed in US 4100200 Additionally, as disclosed in UK Patent Application No 0616865.2, sulfonyl ethers may be used in the synthesis of HI 6, a bis-pyridinium oxime antidote to certain organophosphate nerve agents As a result of the utility of suffonyl ethers in the synthesis of a wide range of compounds, numerous synthetic pathways for sulfonyl ethers have been proposed For example, in US Patent No 4100200 and in Burness, Wright and Perkins, J. Org Che,n 1977, 42, 2910, a synthesis of bts(methylsulfonoxymethyl) ether is disclosed in which acetyl methylsulfonate is reacted with trioxane to form bis(methylsulfonoxymethyi) ether which was then purified.
Further examples of syntheses of sulfonyl ethers are provided in Japanese Patent Nos. 03-178958, 03-178959, 03-123768 and 03-123769 In each of those patents, pathways for producing sulfonyl ethers from acetoxymethanesulfonate are disclosed.
While the synthetic pathways disclosed in the above-mentioned documents result in sulfonyl ethers of acceptable purity for use in the field of photography, in other fields, the purity requirement will be higher. It would therefore be desirable to provide a synthesis of high purity sulfonyl ethers Thus, according to a first aspect of the present invention, there is provided a method of preparing a sulfonyl ether comprising the steps of i) reacting a sulfonic acid with an anhydride, under continuous vacuum distillation conditions, to form a carboxysulfonate, ii) reacting the carboxysulfonate with an optionally substituted cycloalkane ring containing at least 3 heteroatoms to form a sulfonyl ether pre-mix comprising a sulfonyl ether and at least two additional reaction products each containing at least one ether linkage; iii) subjecting the pre-mix to continuous vacuum distillation conditions to remove at least some of the additional reaction products from the sulfonyl ether pre-mix to provide a crude sulfonyl ether product; and iv) purifying the crude sulfonyl ether product.
Using this process, sulfonyl ether products having a purity of greater than 97% have been obtained It will be understood by those skilled in the art that such high purity products may be used in the synthesis of a wider range of compounds than the sulfonyl ethers prepared according to the prior art methods discussed above In preferred embodiments, the sulfonic acid has the formula.
R1-S-OH wherein R1 is selected from the group consisting of hydrogen, substituted and unsubstituted branched and straight-chain alkyl, alkoxy, haloalkyl, alkoxylated alkyl, alkoxylated alkoxy, alkylamino, substituted and unsubstituted cycloalkyl, substituted and unsubstituted cycloalkylamino, substituted and unsubstituted carbocyclic aryl, substituted and unsubstituted carbocylic aryloxy, substituted and unsubstitufed heteroaryl, substituted and unsubstituted carbocylic arylamino and substituted and unsubstituted heteroarylamino, wherein the or each heteroatom is independently selected from sulphur, nitrogen and oxygen In a most preferred embodiment, R1 is alkyl, more preferably methyl In a preferred embodiment the anhydride has the formula R2OR2 wherein R2 are the same or different and are selected from the group consisting of hydrogen, substituted and unsubstituted branched and straight-chain alkyl, alkoxy, haloalkyl, alkoxylated alkyl, alkoxylated alkoxy, alkylamino, substituted and unsubstituted cycloalkyl, substituted and unsubstituted cycloalkylamino, substituted and unsubstituted carbocyclic aryl, substituted and unsubstituted carbocylic aryloxy, substituted and unsubstituted heteroaryl, substituted and unsubstituted carbocylic arylamino and substituted and unsubstituted heteroarylamino, wherein the or each heteroatom is independently selected from sulphur, nitrogen and oxygen In the most preferred embodiment, R2 is alky, more preferably methyl.
Preferably, the carboxysulfonate has the formula:
R H0 2
wherein R1 and R2 are as identified above The optionally substituted cycloalkane ring may take any form provided that it does not adversely affect the purity of the final sulfonyl ether The cycloalkane ring is preferably 4 to 10 membered. The cycloalkane ring may be substituted with any substituent selected from the group consisting of hydrogen, substituted and unsubstituted branched and straight-chain alkyl, alkoxy, haloalkyl, dikaxylated aikyl, alkoxyted aikoxy, alkyiduhirlo, substituted dnd unsubstituted cycloalkyl, substituted and unsubstituted cycloalkylamino, substituted and unsubstituted carbocyclic aryl, substituted and unsubstituted carbocylic aryloxy, substituted and unsubstituted heteroaryl, substituted and unsubstituted carbocylic arylamino and substituted and unsubstituted heteroarylamino, wherein the or each heteroatom is independently selected from sulphur, nitrogen and oxygen However, it is especially preferred that the cycloalkane ring is unsubstituted. For example, the cycloalkane ring may be trioxane or tetraoxane In a most preferred embodiment, the cycloalkane ring is trioxane In a preferred embodiment, the sulfonyl ether has the formula: 1? ii R1 S R1 0 0 wherein R1 is as identified above Most preferably, the sulfonyl ether is bis(methanesulfonylmethyl)ether The pre-mix includes at least two reaction products besides the sulfonyl ether, which each contain at least one ether linkage The most likely additional reaction products which will be included in the pre-mix will have the formula: OO R2 R O R
S
wherein R2 is as identified above.
These additional products are removed using continuous vacuum distillation conditions and may be discarded or utilized in other syntheses.
The continuous vacuum distillation conditions used in steps i) and I or iii) may be provided using any apparatus known in the art which does not adversely affect the purity of the final sulfonyl ether product However, in preferred embodiments, the continuous vacuum distillation conditions are provided using wiped film evaporator apparatus.
The crude sulfonyl ether product may be purified in any way. Preferably, a solvent / anti-solvent combination is employed For example, the solvent / anti-solvent combination may be applied to the crude product to separate the sulfonyl ether product from impurities The sulfonyl ether product could then be subjected to low temperature conditions to yield sulfonyl ether crystals which could then be filtered off, leaving the solvent and any other impurities. Additionally, the sulfonyl ether crystals could be washed to remove any adhered solvent / impurity In a particularly preferred embodiment, the crude sulfonyl ether product is charged to 1,2-dimethoxyethane (1 lwt) at ambient temperature To this a solvent I anti-solvent combination, for example a mixture of diisopropyl ether (i.Owt) & tetrahydrofuran (0 O6wt), may be charged whiie maintaining the temperature at 10 to 15 C Seed crystals may be added and crystallization occurs in this temperature range The resulting slurry is cooled to 0-5 C and stirred, preferably for at least an hour It is then filtered and rinsed with, for example, DIPE/THF mixture (2x1.Owt). The slurry is then filtered again, in a pressure (PALL) filter and is not exposed to air/moisture The resulting cake is dried under a nitrogen stream.
The invention will now be more particularly described with reference to the
following example
Example I
Synthesis of bis (met hanesulfonylmethyl) ether from the reaction of acetoxymethanesulfonate with tnoxane utilising continuous vacuum distillation Step 1 Synthesis of Acetoxymethanesulfonate (AMS) o o 0 0 0 0 S-C H + conbnuousd istiilation \O + OH t 0 0 removed by distiiIaton acetoxymethanesulfonate (AMS) To acetic anhydride (AA) (1751 g, 17 1 mols, 3 mol equiv) in a flask is added methanesulfonic acid (MSA) (550 g, 5 7 mols, 1 mol equiv) with stirring The resulting yeliow solution is suited for 20-30 miii The material is then pumped into an apparatus suitable for continuous vacuum distillation (wiped film evaporator 2 inch [5 cm] column diameter, flow rate, 9.9 mI/mm). After appropriate priming of the apparatus distillate (1546 g) and residue (713 g) are collected The residue is analysed by 1H nmr (wlw%) 93.6 AMS, 4 0 MSA, 1 4 AA, 0.6 AcOH Step 2 Reaction of crude AMS with tnoxane o o + . rMSOOOMS + AcO0Ac mixed ethersl o BSME pre-mix To crude AMS (710 g, 4.83 mol AMS) with good stirring was added solid trioxane (222 3 g, 2 47 mol, 0 5 mol equiv relative to AMS + AA) at such a rate to maintain a temperature of 60-65 C At the end of the addition the reaction rn,xture was stirred for approximately 2 h at 60 C Analysis of this material by 1H nmr revealed it to be a complex mixture of mixed sulfonyl and acetyl ethers, methylene diacetate and product bis(methanesulfonylmethyl)ether BSME Step 3 Continuous vacuum distillation of the BSME pre-mix from step 2 n---r---np + Ar(I OAr BSME pre-mix -.* crude BSME oil removed by distillation The crude BSME pre-mix liquid (932.6 g) is pumped into an apparatus suitable for continuous vacuum distillation (wiped film evaporator 2 inch [5 cm] column diameter, flow rate, 9 9 mI/mm) After appropriate priming of the apparatus distillate is collected (270 g) and residue (573 g) The residue is analysed by 1H nmr (w/w%) 62 6 BSME.
Step 4 Crystallization/purification of BSME MsOOOMs crystaIhsationfsoiation MsOOOMs crude BSME oil bis(methanesulfonyimethyl)ether BSME Crude BSME (345g, 626 %w/w) is charged to 1,2-dimethoxyethane (385g) at ambient temperature To this a mixture of diisopropyl ether (361g) and tetrahydrofuran (19g) are carefully charged whilst maintaining the temperature at 10-15 C Some BSME seed crystals are added and crystallisation occurs in this temp range The slurry is cooled to 0-5 C and stirred for another hour, filtered and rinsed with DIPE/THF mixture (2x340g) The slurry is filtered in a pressure (PALL) filter and is not exposed to air/moisture The pale brown cake (165g) is dried under nitrogen stream ready for the next step of the process nmr CDCI3 553 CH2O (4H), 3.13 OS(O)2CH3(6H)

Claims (1)

1 A method of preparing a sulfonyl ether comprising the steps of.
i) reacting a sulfonic acid with an anhydride, under continuous vacuum distillation conditions, to form a carboxysulfonate; ii) reacting the carboxysulfonate with an optionally substituted cycloalkane ring containing at least 3 heteroatoms to form a sulfonyl ether pre-mix comprising a sulfonyl ether and at least two additional reaction products each containing at least one ether linkage, iii) subjecting the pre-mix to continuous vacuum distillation conditions to remove at least some of the additional reaction products from the fri n ii,i+ ke, r n rn rn iv fri nm, rl r, .-i-i rI I tu r I I Ifru ruu ii,+k ni r n rrurl i p nI n in I Ji iy I u.. LI IL I JI L.I I IA LIJ Li V Ii..1L (A i..tI LILIL. ..LII I LII iy I L. LI IL.I JI 4L1L.L, CU ILl v) purifying the crude sulfonyl ether product 2. The process of Claim 1 wherein the methanesulfonic acid has the formula R1-S-------OH wherein R1 is selected from the group consisting of hydrogen, substituted and unsubstituted branched and straight-chain alkyl, alkoxy, haloalkyl, alkoxylated alkyl, alkoxylated alkoxy, alkylamino, substituted and unsubstituted cycloalkyl, substituted and unsubstituted cycloalkylamino, substituted and unsubstituted carbocyclic aryl, substituted and unsubstituted carbocylic aryloxy, substituted and unsubstituted heteroaryl, substituted and unsubstituted carbocylic arylamino and I () substituted and unsubstituted heteroarylamino, wherein the or each heteroatom is independently selected from sulphur, nitrogen and oxygen.
3 The process of Claim 2 wherein R1 is methyl.
4 The process of any one of Claims 1 to 3, wherein the anhydride has the formula R2 R2 wherein R2 are the same or different and are selected from the group consisting of hydrogen, substituted and unsubstituted branched and straight-chain alkyl, alkoxy, haloalkyl, alkoxylated alkyl, alkoxylated alkoxy, alkylamino, substituted and unsubstituted cycloalkyl, substituted and unsubstituted cycloalkylamtno, substituted and unsubstituted carbocyclic aryl, substituted and unsubstituted carbocylic aryloxy, substituted and unsubstituted heteroaryl, substituted and unsubstituted carbocylic arylamino and substituted and unsubstituted heteroarylamino, wherein the or each heteroatom is independently selected from sulphur, nitrogen and oxygen The process of Claim 3 wherein R2 is methyl.
6 The process of any one of Claims 1 to 5, wheiein the carboxysuifonate has the formula. R2
7 The process of Claim 6 wherein the carboxysulfonate is acetyl methane sulfonate 8 The process of Claims 1 to 7 wherein the cycloalkane ring is trioxane 9. The process of any one of Claims 1 to 8, wherein the sulfonyl ether has the formula.
R1 o o S-R1 The process of any one of Claims 1 to 9 wherein the sulfonyl ether is bis(methanesulfonylmethyl)ether.
11 The process of any one of Claims 1 to 10 wherein the continuous vacuum distillation conditions used in steps i) and I or iii) are provided using wiped film evaporator apparatus.
12 The process of any one of Claims 1 to 11 wherein the crude sulfonyl ether product is purified in step iv) using a solvent / anti-solvent combination
GB0700515.0A 2007-01-11 2007-01-11 Improved synthesis for the preparation of sulfonyl ethers Expired - Fee Related GB2445617B (en)

Priority Applications (8)

Application Number Priority Date Filing Date Title
GB0700515.0A GB2445617B (en) 2007-01-11 2007-01-11 Improved synthesis for the preparation of sulfonyl ethers
CA002674873A CA2674873A1 (en) 2007-01-11 2008-01-08 Synthesis of a bis (sulfonyl) ether from sulfonic acid via the corresponding carboxysulfonate
EP08701318A EP2121587A1 (en) 2007-01-11 2008-01-08 Synthesis
AU2008204534A AU2008204534B2 (en) 2007-01-11 2008-01-08 Synthesis
PCT/EP2008/050152 WO2008084048A1 (en) 2007-01-11 2008-01-08 Synthesis
JP2009545169A JP2010515703A (en) 2007-01-11 2008-01-08 Synthesis method
CNA2008800020582A CN101610994A (en) 2007-01-11 2008-01-08 Synthesize two (alkylsulfonyl) ethers from sulfonic acid via the corresponding carboxylic acid sulphonic acid anhydride
US12/522,899 US20100094038A1 (en) 2007-01-11 2008-01-08 Synthesis

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB0700515.0A GB2445617B (en) 2007-01-11 2007-01-11 Improved synthesis for the preparation of sulfonyl ethers

Publications (3)

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GB0700515D0 GB0700515D0 (en) 2007-02-21
GB2445617A true GB2445617A (en) 2008-07-16
GB2445617B GB2445617B (en) 2012-02-15

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US (1) US20100094038A1 (en)
EP (1) EP2121587A1 (en)
JP (1) JP2010515703A (en)
CN (1) CN101610994A (en)
AU (1) AU2008204534B2 (en)
CA (1) CA2674873A1 (en)
GB (1) GB2445617B (en)
WO (1) WO2008084048A1 (en)

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4100200A (en) * 1975-07-21 1978-07-11 Eastman Kodak Company Use of novel ethers as oxydimethylating agents
US5130438A (en) * 1985-11-20 1992-07-14 The United States Of America As Represented By The Secretary Of The Army Bis-methylene ether pyridinium compound preparation

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4008271A (en) * 1974-03-18 1977-02-15 Ethyl Corporation Process for preparing a mixed anhydride of a sulfonic acid and a carboxylic acid
JPH03123768A (en) 1989-10-06 1991-05-27 Konica Corp Production of bisalkylsofonoxymethyl ethers or bisarylsulfonoxymethyl ethers
JPH03123769A (en) 1989-10-06 1991-05-27 Konica Corp Production of bismethylsulfonoxymethyl ether
JPH03178959A (en) 1989-12-07 1991-08-02 Konica Corp Production of bisalkylsulfonomethyl ethers or bisarylsulfonoxymethyl ethers
JPH03178958A (en) 1989-12-07 1991-08-02 Konica Corp Production of bisalkylsulfonoxymethyl ethers or bisarylsulfonoxymethyl ethers

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4100200A (en) * 1975-07-21 1978-07-11 Eastman Kodak Company Use of novel ethers as oxydimethylating agents
US5130438A (en) * 1985-11-20 1992-07-14 The United States Of America As Represented By The Secretary Of The Army Bis-methylene ether pyridinium compound preparation

Also Published As

Publication number Publication date
AU2008204534B2 (en) 2012-06-21
GB2445617B (en) 2012-02-15
GB0700515D0 (en) 2007-02-21
JP2010515703A (en) 2010-05-13
AU2008204534A1 (en) 2008-07-17
US20100094038A1 (en) 2010-04-15
CA2674873A1 (en) 2008-07-17
EP2121587A1 (en) 2009-11-25
CN101610994A (en) 2009-12-23
WO2008084048A1 (en) 2008-07-17

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